Expanded Dengue Syndrome with Gastrointestinal, Cardiovascular, Ocular, and Pulmonary Manifestations: A Systematic Review of Case Reports and Case Series

Abstract

Context: Dengue fever is an acute febrile illness caused by a virus in the Flaviviridae family. Transmission to humans occurs primarily through the bite of infected Aedes mosquitoes. Expanded dengue syndrome encompasses atypical and rare manifestations of dengue fever involving vital organs, including the heart, liver, kidneys, eyes, lungs, and brain. This systematic review aims to summarize the gastrointestinal, cardiovascular, ocular, and pulmonary manifestations of expanded dengue syndrome reported worldwide. Evidence Acquisition: This systematic review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. We systematically searched PubMed, EMBASE, and Web of Science for studies published between January 2000 and December 2024. English-language case reports and case series involving patients with laboratory-confirmed dengue infection and gastrointestinal, cardiovascular, ocular, or pulmonary manifestations were included. Two reviewers independently screened studies, extracted data, and assessed study quality using the Joanna Briggs Institute (JBI) Critical Appraisal Checklist. Results: A total of 120 studies encompassing 157 individual cases met the inclusion criteria. Most reports originated in India. The most frequently reported presentations of expanded dengue syndrome were ocular (36.5%), respiratory (28.3%), gastrointestinal (18.9%), and cardiovascular (16.3%) manifestations. The most common complications within these categories were maculopathy, pleural effusion, pancreatitis, and myocarditis, respectively. Fever occurred in 22.9% of patients with ocular involvement and in 84.6% of patients with cardiovascular manifestations. Thrombocytopenia was least common in ocular cases (27.6%) and most common in gastrointestinal cases (80%). Discussion: This review highlights the clinical significance of expanded dengue syndrome and the need for early recognition of atypical presentations. Greater awareness of organ-specific complications may facilitate timely diagnosis, risk stratification, and management of severe dengue infections.